Question

Stop #3 (watch Video #4B): Walk up the wash until it makes a sharp bend to the right, with a big cliff on the left (west). We will refer to

this spot as "Big Bend". And you get to meet Lily at this stop! Our first challenge is to determine the orientation (strike and dip) of the layering. The video will show you two examples to get you calibrated. Make sure you are watching the video looking to the north!! Watch Video #5B:Now please determine the orientation of the layering in the cliff: Dip =______ strike _____(Note that this video is looking to the west (not north). So you need orient your screen so that you are also looking west!); What type of rock is the more resistant (harder), coarse-grained, tan-colored layer?_________-What type of rock is the less resistant (softer), very-fine-grained, gray-colored layer?_________ Watch Video #6B:These layers belong to the Amole Arkose. This unit accumulated during the early part of the Cretaceous Period, which is a time when southern Arizona was much wetter than today. There were large rivers, big lakes, shallow seaways, and lots of dinosaurs roaming the hills! This video highlights the fine banding that occurs within each of the sandstone layers. These fine bands are called “cross beds" and they tell you that the sediment accumulated in an area of flowing water. You can also tell you the direction of the ancient flow – it is straight down the slope of the fine banding. So this tells you that during accumulation of the Amole Arkose, rivers flowed to the_______.or south)? Recall that we are looking toward the west....(пorth

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